Sound muffler



. Jan. 3, 1928. 1,655,194

J. F. NEWSQM SOUND MUFFLER Filed April 21, 1925 '3 Sheets-Sheet l 1W k 24 a 4 13' I L2- J INVENTOR ATTURHEYS Jan. 3, 1928. 1,655,194

J. F. NEWSOM sour'w MUFFLER I Filed April 21, 1925 '3 Sheets-Sheet 2 a9 4 r J 3 A Patented Jan. 3, 19 28.

JOHN F. NEWSOM, OF PALO ALTO, CALIFORNIA.

SOUND MUFFLER.

Application fled April 21, 1925. Serial No. 24,868, I

The invention relates to means for minimizing or reducing the volume of sound 'entering a room or apartment through a ventilating opening.

An object of the invention is to provide means for intercepting the sound waves traveling toward or through the ventilating opening to reduce the sound disturbance in the room. 1

Another object of the invention is to provide a sound muflier constructed either to reflect or absorb sound waves directed toward or through the opening, or to both reflect and absorb the sound waves either before or after they have passed through the opening, to minimize the sound disturbance within the room.

Another object of the invention is to provide a simple sound intercepting device for use in connection with a window arranged in an opening in a thick wall.

Another object of the invention is to pro vide a window with a sound intercepting device which does not present an unsightly appearance on the exterior or interior of the building.

The invention possesses other advantageous features, some of which with the foregoing will be set forth at length in the following description where I shall outline in full that form of the invention which I have selected for illustration in the drawings accompanying and forming part of the present specification. In said drawings I- have shown several forms of devices embodying my invention, but it is to be understood that I do not limit myself to'such forms since the invention, as set forth in the claims, may be embodied in a plurality 40hr other forms.

The roar of sound from the street which enters the open windows of oflice buildings, hotels, hospitals and homes is very annoying and it is an object of the present inven- 4 5 tion to intercept the sound waves which ordinarily enter the roomthrough open windows and thus reduce or minimize the an.- noyance. These sounds emanate principally from certain sources in the street, such as street car tracks and crossings and moving street cars and; automobile horns, and the device of my invention is arranged to intercept the direct sound waves from these sources, and also to intercept reflected sound waves which are' directed toward the opening in the window. Noises also enter rooms through open transoms and other openings provided for establishing ventilation. By eliminatlng or reducing the intensity of these sound waves, the volume of sound entering the room is very greatly reduced and the annoying effect of the loud and harsh sounds is practically eliminated.

Efl'orts made in the past to minimize the eifect of outside noises which enter rooms have consisted of reflectors arranged to place the window opening in the sound shadow or of sound absorbents in the room placed on the ceilings and walls thereof, to absorb vthe sound energy after it has passed into and spread through the room; whereas in my invention I deal with and nullify the objectional elfects of the entering sound while the sound energy is in immediate proximity to the window opening, in its most confined space and wherein consequence devices for nullitying its eflect can be most efficiently brought to bear upon it.

In accordance with my invention, I arrange sound mufiling or nullifying vmeans adjacent the opening, so that the sound waves are acted upon while they are confined to a small area. These devices comprise a sound shield on the outside of the opening or window to intercept sound traveling toward the opening and devices within t e room adjacent the opening to either absorb or reflect back through the opening, or both absorb and reflect back sound waves which pass through the opening. These absorbing or reflecting devices are arranged within the room adjacent the opening, so that they are in the ath ofthe waves passing through the con ed space of the opening, so that a large portion of the sound which passes through the opening is either reflected back through the opening or absorbed or both. These devices are spaced away from the opening a suificient distance to permit of ventilation and are so arran ed as to minimize the amount of sound which enters the room.

Several forms of devices for accomplishing this result are shown in the accompanying drawings in which:

Figure 1 is a sectional perspective view of a window open at the top and bottom and provided at the top with means for ing and provi ed at the bottom with provided with means ing deadening and reflecting back the sound waves which ass through the upper opena sound shield which is interposed between the opening and the source of sound.

Figure 2 is asectional perspective view of an open window, the lower opening being provided with a sound shield positioned to place the lower opening in the sound shadow and in which the upper opening is provided with a sound shield for placing it in the sound shadow, with sound deadening and reflecting means for further reducing the volume of sound directed toward the opening. and with sound deadening and reflecting means arranged within the room adjacent the opening and with a reflecting device for reflecting back any sound waves which pass the latter deadening and reflecting device.

Figure 3 is a sectional perspective view of an open window provided with devices of my invention, the lower opening being for placing the-opening in the sound shadow and the upper open- 1 ing being provided with means for placlng the opening in the sound shadow, for absorbing sound waves which strike the lower side of the upper surface of the opening and with means arranged within the room adjacent the openin for deadening and reflecting back throng 1 the opening sound waves which enter through the opening.

Figure 4 is a sectional perspective view of an open window ShOWiIlg the lower openprovided with means for placing the opening in the sound shadow and with means for reflecting back sound which passes throu h the opening, and the upper opening provided with means for deadening and reflecting back through the opening sound waves which enter through the opening, in combination with a reflector for reflecting back through the opening sound waves which pass by the deadening and reflecting device. Figure 5 is a sectional perspective view of an open window, showin the lower opening provided with means within the room for reflecting back through the opening sound waves which enter through the opening and showing the upper opening provided with means for reflecting back and absorbing sound waves which are directed toward the under surface of the upper side of the opening and with means within the room for receiving and absorbing the sound waves which pass through the opening.

Figure 6 is a sectional perspective view of an open window, showing the lower opening provided with means for placing the opening in the sound shadow and showing the upper opening provided with means for placing such opening in the sound shadow, together with means for absorbing and reflecting back through the openings, sound waves which enter through the openings.

' from a point outside the window. Since,

This type of construction is particularly advantageous in windows in the higher stories of ofice buildings.

Figure 7 is a sectional perspective view of the upper portion of a window opening, showing a sound absorbing and reflecting device arranged within the room.

The device of my invention is constructed to reduce to aminimum the amount of sound entering a room through a window opened to provide ventilation. This is accomplished by a combination of sound interceptors which first reduce the amount of sound passing through the opening and then intercept the reduced volume of sound which has passed through the opening at a point adjacent the opening, sound from entering the room. .The device for accomplishing this result may be arranged in. various combinations, and in the various figures of the drawings I have shown various combi ations which cooperate in different ways t o produce the desired result. In each of the figures I have shown the device in association with an open window, arranged in a thick wall 2, but it is to be understood that the invention is not limited and thus prevent this to use in connection with windows set in thick walls. The window frame 3 is preferably set in the opening in a plane spaced inward from the outer surf-ace of the wall, so that the movable sashes 4 and 5 are spaced inward from the outer surface of the wall 2. The opening in the wall is provided with a si'll or bottom surface 6, with a top surface 7, and with side walls 8. The various figures of the drawings are perspective views takfen or optimum ventilation, it is desirable to open the window both at the top and the bottom, I have shown the devices of my invention in cooperation with the top and bottom openings, but it is to be understood that I do not limit myself to sound muflling devices associated with both the top and the bottom openings since devices associated with one oppning only may be employed when desira e.

In the construction shown in Figure 1, the lower opening in the window is placed in the sound shadow by a sound intercepting plate 12, which is. positioned between the opening and the source of sound. .This plate 12 may consist of a plate of glass, arranged within the opening in the wall and extending across the opening from side wall to side wall and preferably resting against the bottom wall 6. The side walls of the open- .mg

in the wall prevent sound travelinglongitudinally along the street from entering the window opening, but when the wall is not sufiiciently thick topermit the sound interceptingp'late to be arranged in the window opening, side walls such as shown in the Parker Patent No. 1,108,613 may be ranged within the room used. The plate. 12 is preferably mounted in guides or supports 13, the space between the late and the support being filled with ruber or other conformable material, to damp en any vibrations which may be set up in the plate 12. The supports 13 are prefer- Th ably hinged or pivoted at their lower ends so that the plate 12 may be adjusted to' any desired angle and so that the plate may befolded to inoperative position when desired. The plate 12 may intercept and collect rain and for that reason is provided along its lower edge with vents-12 to discharge the collected water. The under surface of the upper side 7 of the Opening in the wall, on one or both sides of the frame 3, is covered with a sound deadening or absorbing material 14, such as felt or sponge rubber, so that a portion of the sound st'riking this surface at an angle will be absorbed and not reflected through the opening into the room. The sound absorbent may consist of any well known sound absorbent such as hair felt or mineral wool, but I prefer soft sponge rubber on account of its resistance to moisture, the ease with which it can be attached and the fact that it can be, produced in any with surrounding objects. The sound absorbing material 14 at the top of the opening is preferably protected from rain by the drip plate 9, projecting outward from the wall. Arranged within the room adjacent the window openingand extending across the. o ening'at the top thereof is a sound shiel comprising a plate 15, 1 preferably formed of metal, covered with a sound deadening or absorbing material 16, which will cause the amount of sound distributed into the room to be greatly reduced. The major portion of the sound which passes by the interceptor 15 is directed downward, substantially vertically, and this sound is reflected outward through the bottom opening in the window by the reflector plate 17 extending across the opening in the wall adjacent the lower opening of the window and inclined to reflect outward any vertical or substantially vertical sound waves striking it.

1n the construction shown in Figure 2, the arrangement of the elements at the lower opening of the window is substantially the same as that shown in Figure 1, with the exception that the reflector 18 which is aradjacent the lower opening, is substantially vertical, so that it will reflect outward sounds which enter through the opening at the lower part of the window. In this construction, a sound interceptor or sound shield 21, preferably comprising a curved sheet of glass extending across the opening in the wall, is arranged between the-"upper openlng in the window and the source ofsound, to reflect desired color to harmonize backward toward the source of sound, sound waves which are traveling toward the opening in the window. This shield 21 is s downward from the upper surface 7 of the opening to provide for ample ventilation. e upper surface 7, in addition to being provided with sheets of sound absorbing material 22, similar to the sheet 14 disclosed in Fi ure 1, is provided with one or more curved sound reflecting vanes 23 which reflect backward sound-waves which are travelin toward the upper surface 7 of the win ow opening. Since the line of direction of sound from the source lies at a different angle for different altitudes of the window, the shield 21 is pivotally mounted and is adjustable about its pivot,so that it may be moved to lie between the opening at the top of the window and the source of sound. Arranged within the room adjacent the top window opening and spaced from is a sound shield 24, preferably comprising a metallic plate covered with a sound deadening or absorbing material and this plate preferably is curved inward toward the window sash at its lower edge to reflect backward through the window opening sound which enters through the opening. The refiector' 24 is shown extended past the plane of section to show the end or side wall 24 which acts to prevent the lateral travel of sound into the room and such end walls are preferably provided on all of the reflecting and absorbing devices shown in the drawings to prevent lateral dispersion of the sound. l/Vhen desirable, the pocket or recess formed by the reflector or absorber may be covered at its open side with a thin cloth or screen or other fabric to keep dust and insects and birds from the insides of. the recesses. Sound will pass the shield 24 and move downward into the room and a curved reflector 25 is arranged adjacent the Window sash below the shield 24 to reflect backward into the opening in the interceptor 24. The reflector 25 iscurved so that the reflected sound from all points thereof is directed toward the upper window opening.

The construction shown in Figure 3 is a modification of that shown in Figure 2, in which the outside shield 26, guarding the lower opening in the Window, is arranged substantially vertical. Since sound waves usually emanate from a source in the street, which is at a lower level than the windows, the vertical shield 26 will place the lower window opening in the. sound shadowand reflect away from the window the sounds which strike the shield. The upper opening in the window is shielded by the inclined shield 27 which places the upper opening in the sound shadow. Some sound may be repacedwindow, the major I portion ofthe sound which passes by the inward thereflected from the shield 27 substantially ver- 29 of sound deadening material to minimize the amount" of reflected sound which will pass through the upper window opening. Arranged the sash and positioned adjacent the upper window opening is a sound trap or sound 'deadening device which will absorb a large proportion of the sound entering through the top window opening. This sound deadening device comprises a plurality of curved vanes 31 extending across the window opening and covered with a sound deadening material. The sound is trapped between the vanes and its energy is spent, so that substantially all of the sound is absorbed. The vanes gradually approach each other as they progress inwardly, providing troughs of decreasing depth into which the sound waves travel.

' vided into a plurality of pockets by the vertically'spaced walls 30, which are also covered with sound deadening material." The sound is trapped in the pockets and the unabsorbed portions rebound-from the surface again strike deadening material. The pockets decrease in size rearwardly, so that in eflect the sound waves are led into and absorbed in a funnel lined with sound absorbing material. The sound waves mayrebound a plurality of times but become weaker at each-rebound,

so that substantially all of the sound is ab- 3 window opening substantially "the same as.

'sorbed.

The construction shown in Flgure 4, is provided with an arrangement at the bottom that shown in Figure 2, with the exception that the inside reflector 32 at the bottom window opening is curved toward the sash the bottom window opening soun enters through the'lower window opening. The reflector 32 is preferably arranged in a pocket 32 into which it may be lowered when desired, any suitable type of raising- A plurality of curved plates device being 'usedfor that purpose.

' suitable. form of device may be constructed along the lines of the devices now used for raising and lowering automobile windows.- In this construction also the exterior sound shield is omitted at the top window opening and the sound which enters through such opening is deadened by the sound trap the opening in the wall at the top there; of and spaced from the' window. This trap comprises a box-like structure having a front wall formed of a plurality of wedges 34 of a sound deadening material, which absorbing material such as felt or within the room and spaced from These troughs are preferably di- 33 extending across form between them a plurality of funnels 34*, open at their ends. The back of the box is lined with a layer 34 of sound deadening material which'is spaced away from the bottoms of the funnels to form an expansion chamber for the sound which passes through the funnels and such sound is substantially entirely absorbed in said chamber. The sound is largely deadened by contact with the walls of the funnels and the remaining sound is deadened in the expansion chamber. Since this structure employs no outside sound interceptor, the amount of sound which will pass downward between the absorber 33 and the window will be greater than that which will pass by the absorber shown in Figure 3 and, to prevent this sound from entering the room, a curved reflector 35 is arranged adjacent the sash to reflect upward and outward through the window opening sound which passes the absorber 33 and strikes the reflector 35. The reflector 35 is pivoted at its lower edge so that it may be swung to adjusted positions or so that it may be swung upward agiiinst the sash when its use is not desirab 6.

In the structure shown 'in Figure 5 theplate 36 is preferably formed of glass and is set in a conformable material such as rubber, so that any vibrations which may be induced therein are deadened. At the upper window opening, curved reflectors 37 are arranged to reflect backwardly sound waves which are directed toward the upper surface 7 of, the opening. These sound waves are further deadened by a strip of sound absorbing material 38 arranged at the bases of the vanes 37 Arranged within the room adjacent the upper window opening and extending across the opening in the wall and spaced backward from the window frame 3 is a sound absorbing device com rising a 41 of ecreasm distance apart backwardly,

so that funne shaped passages are provided between the;

plates. The sound enters these funnel shaped passages or horns and is conducted to the small ordischarge gend thereof where it is discharged into a box 42; containing a sound absorbing or .deadening' naterialii.

dow is the same as in' Figure 4. At the top of the window, however, the top window opening is placed in the sound shadow by the substantially horizontal plate or shield In the construction shownin Figure 6, -the arrangement at the bottom of the winthe the reflector 46, extending across the opening in the wall and is reflected outwardly by the reflector 46 so that it may not pass downwardly toward the reflector '12 at the bottom window opening. The sound which'enters through the top window opening is trapped by the plurality of vanes 47 extending across the opening in the wall behind the top window opening. These vanes 47 are curved downwardly and approach each other at the back plate 48, and the vanes and the back plate are covered with sound absorbing material, to absorb a large portion of the sound. The vanes 47 are so formed and positioned that any sound which discharges from the pockets between the vanes is directed toward the window opening, .50 that the unabsorbed sound is discharged outward through the window opening. The sound which passes downward in the space between the-window pane and the vanes 47 is largely reflected backward by the reflector 49, which is curved so that the reflected sound is directed through the window open- 1n Tn Figure 7 I have shown a modified form of the sound absorbing and reflecting device which is arranged within the room adjacent the top window opening: This device consists of a back rality of downwardly curved spaced vanes 52 covered with a sound absorbing material. The sound striking these vanes is reflected back and forth in the chambers between the vanes and is thus deadened. The plate 51 is preferably hinged at its upper edge so that the angle of the structure may be varied or so that it may be moved upward out of way when desired. This device may be used in conjunction with the reflector 49 shown in Figure 6, so that unabsorbed sound, striking the reflector 49 will be directed out through the window opening.

I claim:

1. The combination with a wall having an opening to provide ventilation ina contiguous ro'omof a sound absorbing device arranged outside the opening to absorb a portion of the sound which is directed toward the opening, and a sound reflector arranged within the room adjacent the opening to reflect a portion of entering sound backward through the opening.

2. The combination with a wall having an opening to provide ventilation in a contiguous room, of a sound reflector arranged outside the opening to reflect sound directed toward the opening away from the opening and a sound reflector arranged withln the room adjacent the opening to reflect entering sound backward through the. opening.

3. The combination with a wall having an plate 51 provided with a pluadapted provide ventilation, a sound shield arranged opening to provide ventilation in' a contiguous-room, of a sound reflector arranged outside the opening to reflect sound directed toward the opening away from the opening and a sound absorbing device arranged within the room adjacent the opening to absorb a portion of the sound entering through the opening.

4. The combination with a wall having an opening to provide ventilation in a' contiguous room; of a sound absorbing and reflecting device arranged within the room partially absorb adjacent the opening, to and partially reflect back through the opening, sound entering through the opening.

5. The combination with a wall having an opening to provide ventilation in a contiguous room, of a sound absorbing device arranged outside the opening to reduce the volume of sound passing through the opening, and a sound absorbing device arranged within the room adjacent the opening to reduce the volume of the entered sound.

6. The combination with a wall having an opening to provide ventilation in a contiguous room, of a sound reflecting device arranged outside the opening to intercept sound coming toward the opening, a sound reflecting device arranged within the room adjacent to. and spaced from the opening to reflect entering sound backward through the opening and a third sound reflecting device arranged within the room and adjacent the opening to reflect sound which passes the second reflector back toward the opening.

In combination with a wall having an opening, a window opening, a sash arranged in said frame adapted to be moved to open the window at the bottom,"a sound shield spaced from and arranged in front of the lower part of the window and a body of sound deadening material interposed between the bottom of the 'frame and the bottom of the shield. 3 8. In. combination with a wall having an opening, a window frame arranged in the opening adjacent the inner side thereof, a sash arranged in said frame adapted to be moved to open the window to provide ventilation, a sound shield disposed in the opening adjacent the outer side thereof and arranged to intercept sounds coming toward the openin in the window and a body of sound dea ening material arranged in the path of sound which is not intercepted by the shield.

9. combination with opening, a window frame opening,

a wall having an arranged in said a sash arranged in said frame to be moved to open the window to outside the window to intercept sound coming toward the opening in the window, sound deadening material covering the upper surface of the opening in thewall and a frame arranged in the sound shield arranged on the inside'of the window to intercept sound coming through the opening in the window.

'10. The combination with a wall having an opening to. provide ventilation in a. contiguous room, deflector arranged in the room adjacent the opening and adapted to be moved from operative to inoperative position.

approaching vanes on said frame and sound deadening material covering said vanes.

13. The combination with a wall having an opening to provide ventilation in a contiguous room, of a box-like structure arranged in the room adjacent the opening, a plurality of walls in said structure; said walls approaching each other inwardly to provide gradually restricted chambers, and sound absorbing material lining said walls. 14. The combination-with a wall having an opening to provide ventilation in a contiguous room, of a plurality'of spaced walls forming sound pockets arranged in the room adjacent the opening, said pockets being so disposed that sound reflected from them is directed outward through the openlng. I

15. A sound nullifying device comprising 1 a series of vanes lined with sound absorbing materialj'so arranged with relation to each other as to cause a plurality of reflections of sound and maximumabsorption of sound in a minimum s ace.

'16. The combination with a wall having an opening therein to provide ventilation in a contiguous room,

of a vertically movable ,sound raised to open of a concave reflector ar-.

mamas ranged within the room adjacent the opening and positioned to'reflect back through the opening a beam of the sound waves which enter through the opening the reflector.

17. In combination with a wall having an opening, a window frame arranged in said opening, a sash in said frame adapted to be the window at the bottom to provide ventilation and a sound deflector arranged on the inside of the window at the'base thereof, the bottom of the deflector being spaced from'the bottom of the sash to provide an upwardly opening ventilatin passage between the deflector and the'sas and the deflector being arrangedto deflect outwardly through the opening, sound which enters through the opening.

18. The combination with a wall having an opening, a win said opening, and a sash arrangedin said frame ada ted to be moved to open the window, 0 a sound deflector arranged outside the window to deflect sound directed toward the window opening and a sound deflector arranged inside the window with the bottom thereof spaced from the bottom of the sash to permit maximum ventilation through the window opening and the top thereof being spaced-from the plane of the sash a distance not greater than the spacing of the bottom from the plane of the sash,

whereby the' maximum amount of sound is reflected back through the opening.

' 19. A sound minimizing ventilator adapt-- ed to be applied to an opening in the wall of a room comprising means for absorbinga portion of the sound waves tending to enter said opening,'and a transparent shield for reflecting the unabsorbed sound waves in a direction to prevent their entrance into the room.

\ In testimony whereof, I have hereunto set my hand.

JOHN F. NEWSOM.

and strikedow. frame arranged In 

